<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<button onfocus="writeMsg()">按钮</button>
		<button onclick="doit()">点击</button>
		<input onkeydown="writeMsg()" />
		<select onchange="writeMsg()">
			<option>张三</option>
			<option>李四</option>
			<option>王五</option>
			<option>赵六 </option>			
		</select>
	</body>
	<script>
	function doit(){
		alert("你好");
	}
	function writeMsg(){
		console.log(111)
	}
	
	
	</script>
</html>
